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FIELD  MUSEUM  OF  NATURAL  HISTORY 

CHICAGO 

1922 


THE  UNIVERSITY 

OF  ILLINOIS 

LIBRARY 

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MAMMALS  OF  THE 
CHICAGO  AREA 


BY 

COLIN  C.  SANBORN 
Assistant,  Division  of  Mammals 


'^f  <i'''-^f  OF  THr 
/'■PR  2"  1928 


Zoology 

Leaflet  8 


FIELD  MUSEUM  OF  NATURAL  HISTORY 

CHICAGO 

1926 


The  Zoological  Leaflets  of  Field  Museum  are  de- 
voted to  brief,  non-technical  accounts  of  the  history, 
classification,  distribution  and  life  habits  of  animals, 
with  especial  reference  to  subjects  shown  in  the 
Museum's  exhibits. 

LIST  OF  ZOOLOGICAL  LEAFLETS  ISSUED  TO  DATE 

No.  1.  The  White-tailed  Deer $  .10 

No.  2.  Chicago  Winter  Birds ,10 

No.  3.  The  American  Alligator 10 

No.  4.  The  Periodical  Cicada 10 

No.  5.  The  Alligator  Gar 10 

No.  6.  The  Wild  Turkey    ' 10 

No.  7.  The  Man-Eaters  of  Tsavo       •     •    > 50 

No.  8.  Mammals  of  the  Chicago  Area 25 

D.  C.  DAVIES,  Director 


FIELD  MUSEUM  OF  NATURAL  HISTORY 
CHICAGO,  U.  S.  A. 


APS  2 "J  ^926 


-&rr~ 


■       V 


1j 


y 


MAMMALS  OF  THE  CHICAGO  AREA. 

PART  OF  AN    EXHIBIT   IN   FIELD   MUSEUM   OF  NATURAL  HISTORY. 


530 


Field  Museum  of  Natural  History 

DEPARTMENT  OF  ZOOLOGY 
Chicago,  1925 


Leaflet  Number  8 


Mammals  of  the  Chicago  Area 

The  "Chicago  Area"  is,  for  convenience,  regarded 
as  covering  all  territory  within  fifty  miles  of  the  center 
of  the  city  of  Chicago.  Therefore,  it  includes  parts  of 
three  states,  reaching  just  beyond  the  southern  border 
of  Wisconsin  on  the  north  and  extending  southward  to 
the  Dune  Region  and  the  whole  southern  end  of  Lake 
Michigan  in  Indiana.  The  pioneer  student  of  mammals 
in  this  area  was  Robert  Kennicott,  whose  list  of  the 
mammals  of  Cook  County,  Illinois,  published  in  1855,  is 
still  the  most  important  paper  devoted  exclusively  to  the 
area.  Since  his  time,  scattered  observations  have  been 
made,  resulting  in  considerable  additions  to  knowledge 
of  the  subject,  but  no  thorough  study  has  been  carried 
out.  The  present  paper  is  intended  to  summarize  exist- 
ing knowledge  and  to  assist  and  stimulate  local  natural- 
ists who  may  desire  to  pursue  the  subject. 

The  study  of  mammals  is  more  difficult  and  not  so 
easily  entered  into  as  the  study  of  birds.  Most  mam- 
mals are  nocturnal  and  the  diurnal  ones,  in  the  major- 
ity of  cases,  are  shy  and  elusive.  The  different  forms 
to  be  met  with  in  one  region  are  very  limited,  about 
thirty-five  in  the  Chicago  Area  as  compared  to  two 
hundred  and  seventy  birds  occurring  there.  Many 
identifications  depend  largely  upon  dental  or  cranial 
characters  and  require  time  and  work  in  preparing  the 
skull  for  study  and,  in  many  cases,  the  use  of  a  high 
powered  lens  on  the  smaller  skulls,  troubles  not  met  in 
amateur  bird  study.    For  one  outside  a  scientific  insti- 

[129] 


2  Field  Museum  of  Natural  History 

tution,  the  life  histories  and  photography  of  mammals 
might  be  the  easiest  and  most  interesting  branches  of 
the  study.  A  large  percentage  of  the  work  must  be 
done  with  captive  animals,  but  most  animals  are  easily 
tamed  and  make  interesting  pets. 

Of  the  fifty-three  species  of  mammals  formerly 
living  in  northern  Illinois  and  Indiana,  fourteen  have 
entirely  disappeared,  ten  are  now  very  rare,  and  the 

rest  are  waging  a  losing 
battle  with  so-called  civili- 
zation. Many  of  the  larger 
ones  disappeared  from  this 
section  over  a  hundred 
years  ago  and,  today,  only 
a  few  scattered  bones  are 
left  to  show  that  elk,  deer, 
buffalo  and  bear  once  oc- 
curred here.  Wolves,  cou- 
gars, Jynx,  foxes  and  other 
Black  Bear  predatory    animals    were 

soon  driven  out.  These  were  quickly  followed  by  the  val- 
uable fur-bearers,  such  as  the  beaver,  marten,  badger, 
and  otter.  While  some  fur-bearers  of  value  are  left  in 
small  numbers,  the  majority  of  mammals  here  now  are 
small  rodents  of  more  harm  than  benefit  to  man.  The 
two  species  that  thrive  best  are  the  unwelcome  foreign- 
ers, the  House  Rat  and  House  Mouse.  The  next  quar- 
ter century  will  undoubtedly  see  the  ranks  of  the  rab- 
bit, muskrat,  skunk,  coon  and  mink  greatly  thinned,  if 
not  wiped  out  entirely.  The  thirty-nine  species  living 
here,  today,  represent  six  of  the  thirteen  orders  found 
in  North  America.  These  are  the  Rodentia  (gnawers) , 
Lagomorpha  (rabbits),  Carnivora  (flesh-eaters),  In- 
sectivora  (shrews  and  moles),  Chiroptera  (bats),  and 
Marsupialia  (opossums).  These  in  turn  are  divided 
into  superfamilies,  families,  subfamilies,  genera,  sub- 
genera, species  and  subspecies. 

[130] 


Mammals  of  the  Chicago  Area  3 

The  status  of  our  mammal  fauna,  at  present,  is 
indicated  by  the  following  lists: 

IMammals  now  Living  in  the  Area. 

1.  Woodchuck Marmota  monax 

2.  Striped  Gopher Citellus  tridecemlineatus 

3.  Gray  Gopher Citellus  franklini 

4.  Gray  Chipmunk Tamias  striatus  griseus 

5.  Red  Squirrel Sciurus  hudsonicus  loquax 

6.  Gray  Squirrel Sciurus  carolinensis  leucotis 

7.  Fox  Squirrel Sciurus  niger  rufiventer 

8.  Flying  Squirrel Glaucomys  volans 

9.  Northern  White-footed  Peromyscus  leucopus  novebora- 

Mouse censis 

Prairie  White-footed  Mouse .  Peromyscus  maniculatus  hairdi 
Common  Meadow  Mouse. . .  . Microtus pennsylvanicus 

Prairie  Meadow  Mouse Microtus  ochrogaster 

Pine  Mouse Pitymys  pinetorum  scalopsoides 

Muskrat Ondatra  zibethica 

House  Rat Rattus  norvegicus 

House  Mouse Mus  musculus 

Hudson  Bay  Jumping  Mouse.  Zapus  hudsonius 

Mearns's  Cotton-tail  Rsibhit .  Sylvilagus  floridanus  mearnsi 

Raccoon Procyon  lotor 

Bonaparte's  Weasel Mustela  cicognanii 

New  York  Weasel Mustela  noveboracensis 

Least  Weasel Mustela  allegheniensis 

Mink Mustela  vison  mink 

Skunk Mephitis  hudsonica 

Coyote Canis  latrans 

Red  Fox Vulpes  fulva 

Prairie  Mole Scalopus  aquaticus  machrinus 

Star-nosed  Mole Condylura  cristata 

Long-tailed  Shrew Sorex  cinereus 

Short-tailed  Shrew Blarina  brevicauda 

Small  Short-tailed  Shrew. . .  Cryptotis  parva 

Little  Brown  Bat Myotis  lucifugus 

Say's  Bat Myotis  subulatus 

Silver-haired  Bat Lasionycteris  noctivagans 

Brown  Bat Eptesicus  fuscus 

Red  Bat Nycteris  borealis 

Hoary  Bat Nycteris  cinerea 

Rafinesque's  Bat Nycticeius  hurneralis 

Virginia  Opossum Didelphis  virginiana 

Mammals  Extirpated  within  Historic  Times. 

1.  Virginia  Deer Odocoileus  virginianus 

2.  American  Elk Cervus  canadensis 

[  131  ] 


Field  Museum  of  Natural  History 


3.  American  Bison Bison  bison 

4.  Beaver Castor  canadensis 

5.  Eastern  Cougar Felis  couguar 

6.  Canada  Lynx Lynx  canadensis 

7.  Bobcat Lyjix  rufus 

8.  Gray  Fox Urocyon  cinereoargenteus 

9.  Timber  Wolf Canis  nubilus 

10.  Otter Lutra  canadensis 

11.  American  Badger Taxidea  taxus 

12.  Marten Mustela  americana 

13.  Fisher Mustela  pennanti 

14.  Black  Bear Ursus  americanus 

The  order  of  rodents  (Rodentia)  is  well  repre- 
sented and  includes  the  woodchucks,  squirrels,  rats 
and  mice,  all  gnawers.  Members  of  this  order  have 
two  upper  and  two  lower  incisors  with  a  large  gap 
between  them  and  the  cheek  teeth.  They  are,  for 
the  most  part,  vegetable  feeders,  meat  forming  a 
very  small  percentage  of  their  diet,  and  are  all  harm- 
ful to  agriculture.  Among  them  are  found  subterra- 
nean, terrestrial,  aquatic  and  arboreal  mammals. 

The  Flying  Squirrel  is  more  common  in  this  area 
than  is  commonly  supposed,  as  it  is  nocturnal  and 
rarely  ventures  forth  by  day  except  occasionally  in 

very  cloudy  weather.  It  lives  in  old 
woodpecker  holes  and  often  under  the 
eaves  or  in  the  attics  of  houses.  It  is 
very  sociable  and  sometimes  as  many 
as  twenty  will  live  peaceably  together 
in  one  large  hollow.  The  strong,  furred 
membrane  on  each  side,  between  the 
front  and  hind  legs,  enables  it  to  ghde 
or  sail  from  the  top  of  one  tree  to  the 
foot  of  another  which  it  then  ascends 
and  sails  to  the  next  one.  The  food 
of  this  squirrel,  much  like  that  of 
other  squirrels,  consists  of  nuts,  seeds,  insects  and, 
sometimes,  eggs  and  even  young  birds.    From  four  to 


[  132] 


riS!3Hfc  -o^ 


MAMMALS  OF  THE  CHICAGO  AREA. 

PART  OF  AN   EXHIBIT  IN   FIELD  MUSEUM  OF  NATURAL  HISTORY. 


Mammals  of  the  Chicago  Area  5 

six  young  are  brought  forth  in  April  and  are  said  to 
make  very  tame  and  docile  pets. 

Of  the  three  true  squirrels  found  here,  the  North- 
ern Gray  is  perhaps  the  most  common,  having  taken 
man  into  his  confidence  more  than  his  cousins,  the  Red 
and  the  Fox  Squirrels.  Gray  Squirrels  are  common  in 
the  parks  and  suburbs  about  Chicago  and,  as  they  have 
not  been  molested,  have  become  very  tame.  In  the 
woods,  however,  especially  during  the  hunting  season, 
they  are  quite  shy  and  can  dodge  around  a  tree  and 
disappear  in  a  most  surprising  manner.  They  live 
chiefly  upon  nuts  and  seeds  of  trees,  but  occasionally 
eat  small  fruits  and  beetles  and  their  larvae.  In  the 
spring  they  damage  maple  trees  by  girdling  the 
branches  and  drinking  the  sap.  Birds'  nests  also  suffer 
from  them.  In  the  woods,  they  either  live  in  hollow 
trees  or  build  a  large  nest  of  branches,  leaves  and  bark 
or,  with  the  same  material,  roof  over  an  old  crow's 
nest.  In  the  suburbs,  they  often  get  under  the  eaves  of 
houses  and  into  the  walls,  where  they  become  a  great 
nuisance,  especially  early  in  the  morning,  as  they  are 
very  noisy.  There  are  generally  two  litters  a  year, 
one  in  April  and  one  in  September,  of  from  two  to  five 
young. 

The  Fox  Squirrel  is  not  so  common  as  the  Gray, 
and  is  found  farther  away  from  towns.  This  squirrel 
does  not  live  in  colonies.  Each  pair  prefers  its  own 
particular  wood,  and  keeps  all  others  out.  Hollow  trees 
are  their  homes,  although  they  do  build  nests  of  sticks 
and  leaves  for  summer  use.  Like  the  Gray  Squirrel, 
they  do  not  store  food  in  any  one  place  but  bury  nuts 
and  acorns  singly  for  winter  use.  Even  under  deep 
snow,  they  find  at  least  a  certain  part  of  the  nuts  pre- 
viously buried.  Two  litters  of  from  two  to  four  young 
are  born  each  year  and,  when  they  are  old  enough,  they 
are  driven  out  to  fare  for  themselves. 

[133] 


6  Field  Museum  of  Natural  History 

The  Red  Squirrels  are  smaller  than  the  other 
squirrels  that  occur  here,  and  are  most  common  in  the 
Dune  Region.  Like  other  tree  squirrels,  they  live 
mainly  in  woodpecker  holes  and  hollow  trees,  but  they 
have  occasionally  been  noticed  occupying  holes  in  the 
ground.  They  lay  up  large  winter  supplies  of  nuts, 
seeds  and  corn  when  it  can  be  found,  for  while  they 
do  not  mind  the  coldest  weather,  they  prefer  to  stay 
in  on  cloudy  and  stormy  days.  They  are  particularly 
fond  of  pine  seeds,  which  accounts  for  their  abundance 
in  the  Dunes.  During  the  summer,  all  the  wild  fruits 
of  the  woods  are  on  their  menu,  to  which  they  add  in- 
sects, mushrooms,  young  birds  and  eggs.  The  young, 
born  in  April,  number  four  to  five  and,  sometimes,  even 
six. 

A  member  of  the  squirrel  family  that  lives  mainly 
on  the  ground  and  about  stone  walls  and  brush  heaps, 
is  the  Gray  Striped  Chipmunk.  Being  about  ten  inches 

long,  of  a  gray 
brown  color, 
with  two  or 
three  stripes  on 
the  back,  and  a 
slightly  bushy 
tail,  it  is  easily 
recognized  as  it 
darts  under  a 
=  brush    pile    or 

into  its  hole,  uttering  a  sharp  series  of  whistled  alarm 
notes.  It  is  only  seen  from  April  to  the  last  of  October, 
for  during  the  winter  it  hibernates  in  its  burrow  several 
feet  under  ground.  In  the  summer,  it  is  kept  busy  col- 
lecting a  supply  of  nuts,  seeds  and  grain  for  meals  when 
it  wakes  on  warm  days  during  the  winter.  Its  burrow 
runs  down  a  foot  or  two  from  the  opening  and  then 
along  and  upward  to  the  nest  chamber,  with  perhaps  a 


[134] 


Mammals  of  the  Chicago  Area  7 

storehouse  or  two  along  the  way.  There  is  a  back  en- 
trance but  it  is  always  several  rods  from  the  other. 
The  dirt  is  taken  out  in  the  cheek  pouches  and  is  de- 
posited at  a  considerable  distance  from  the  entrances, 
all  possible  care  being  taken  to  conceal  them.  These 
entrances  are  just  large  enough  to  admit  the  animal, 
but  the  burrow  becomes  larger  inside.  Besides  the 
stores  collected  for  winter  use,  the  Chipmunk  eats 
meat,  when  it  can  be  found,  in  the  form  of  young  birds, 
mice  or  snakes.  It  damages  truck  gardens,  eating  all 
kinds  of  berries  and  the  tendrils  of  such  things  as 
peas,  beans  and  cucumbers.  In  spite  of  all  its  faults, 
it  is  a  cheery,  active,  little  creature  to  have  about,  and, 
like  the  squirrels,  it  is  easily  tamed. 

Another  ground  living  species  that  hibernates 
during  the  winter,  is  the  Striped  Gopher.  It  prefers 
the  more  open  country,  while  the  Chipmunk  prefers  the 


more  wooded  areas.  Appearing  about  the  first  of 
April,  it  may  be  seen  until  late  in  October  when  it 
turns  in  for  its  long  winter  sleep.  Gophers  are  larger 
and  heavier  animals  than  Chipmunks  and  the  ears  are 
smaller  and  the  tails  not  so  bushy.  They  have  six 
buffy-white  stripes  on  the  back,  between  which  are 
brown  stripes  with  pale  dots.  Their  burrows  are 
much  alike,  a  long  tunnel  with  store-rooms  and  a  living 
room  or  nest.  They  pass  the  winter  and  bring  forth 
the  young  in  these  burrows.    The  young  arrive  in  May 

[135] 


8 


Field  Museum  of  Natural  History 


or  June  and  average  six  to  seven,  although  ten  have 
been  found.  It  is  almost  three  weeks  before  any  hair 
appears  on  them,  and  they  stay  with  the  female  until 
late  in  the  summer.  Under  such  circumstances  it  is 
only  possible  to  raise  one  litter  a  year.  Before  the 
young  are  born,  and  during  the  time  they  are  with  the 
mother,  the  male  leaves  home  and  shifts  for  himself 
as  best  he  can,  digging  a  summer  home.  Their  food 
consists  partly  of  beetles,  grasshoppers,  caterpillars 
and  weed  seeds,  but,  unfortunately,  they  have  a  fond- 
ness for  grain  and  do  a  great  deal  of  damage  to  crops. 
They  dig  up  the  seed  as  soon  as  it  is  planted,  eat  the 
young  shoots  and,  later,  the  ripened  grain.  Working 
during  the  day,  they  are  ever  on  the  alert,  sitting  up 
to  look  about  for  danger  and,  in  doing  so,  seem  to 
stretch  themselves  to  almost  twice  their  natural  length. 

A  western  species,  whose  range  just  reaches  this 
area,  is  the  Franklin's  Ground  Squirrel  or  Gray  Gopher. 

It  is  chiefly  grayish  in  color,  the  top  of  the  head  being 

blackish  and 
the  tail  gray. 
This  gopher 
is  by  no 
means  com- 
mon and  is 
only  locally 
-"^^    == —  distributed. 

Restless  and  wandering,  it  appears  unexpectedly  in  a 
locality  where  it  may  stay  all  summer  or  only  for  a  few 
weeks.  Its  burrows  are  deeper,  and  it  appears  a  little 
later  in  the  spring  than  the  preceding  species,  but  its 
other  habits  are  practically  the  same.  Both  these 
gophers  cause  no  little  damage  to  golf  courses  when 
they  decide  to  dig  their  burrows  in  a  fairway  or  put- 
ting-green. It  often  takes  several  weeks  before  they 
can  be  discouraged  or  all  caught  in  traps. 


[136] 


Mammals  of  the  Chicago  Area  9 

Each  year  one  of  our  mammals  receives  much  pub- 
licitj^  of  a  doubtful  character.  This  is  the  Woodchuck 
or  Groundhog  that  is  supposed  to  waken  the  second  of 
each  February 
and  come  out  for 
a  look  at  the 
weather  at  noon. 
It  is  doubtful  if 
the  Woodchuck 
realizes  the  g-reat 
responsib  ility 
placed  upon  it. 
However,  after  its 
long  winter  sleep  it  does  come  out  of  its  hole  late  in 
March  when  it  is  much  warmer.  Its  burrows  in  this 
region  are  in  some  small  clump  of  woods  or  ravine, 
easily  accessible  to  a  pasture  or  farmer's  garden.  Dur- 
ing the  summer,  early  in  the  morning  and  late  in  the 
afternoon,  it  comes  out  to  feed  on  the  clover  and  al- 
falfa or  on  almost  any  of  the  vegetables  of  the  garden. 
The  Woodchuck  does  not  store  food  for  \^inter,  so  he 
must  put  on  a  good  layer  of  fat  before  the  first  of 
October  or  whenever  the  first  heavy  frosts  come.  The 
four  to  six  young  are  born  early  in  May,  but  do  not 
get  their  first  look  at  the  world  for  some  four  or  five 
weeks  later.  When  old  enough  to  care  for  themselves, 
they  leave  the  home  burrow  and  find  another  home  in 
some  other  locality.  The  Woodchuck  seems  to  be  a 
heavy,  lazy  animal,  but,  when  cornered,  can  put  up  a 
surprisingly  good  fight. 

Although  the  House  Mouse  and  the  House  or  Nor- 
way Rat  have  been  in  America  since  the  time  of  the 
first  settlers,  they  have  never  made  good  citizens.  The 
House  Mouse  came  originally  from  southern  Asia,  and 
the  Rat  from  Europe,  but  long  ago  they  attached  them- 
selves to  man  and  have  accompanied  him  on  all  his 
travels,  until,  today,  they  are  found  in  all  parts  of  the 


[137] 


10  Field  Museum  of  Natural  History 

world,  not  only  in  the  cities  where  they  are  in  greatest 
numbers,  but  also  in  many  out-of-the-way  places  far 
removed  from  civilization.  They  are  more  prolific  than 
wild  mice  and  reach  maturity  at  an  earlier  age.  The 
House  Mouse  raises  about  five  litters  a  year  of  from 
five  to  nine  young,  and  the  House  Rat  four  to  six  lit- 
ters of  from  six  to  twenty  young.  Both  are  very 
destructive  in  their  search  for  food,  and  the  House  Rat 
is  known  to  carry  fleas  that  are  infected  with  Bubonic 
Plague  germs.  One  cannot  be  too  careful  in  ridding 
the  house  of  the  first  ones  that  appear,  for,  like  the 
House  Fly,  two  mean  a  small  army  in  a  very  short 
time.  Guillotine  traps  and  also  cage  traps,  when  cov- 
ered or  hidden,  are  two  of  the  best  traps  for  catch- 
ing them.  Rats,  like  other  vermin,  increase  under  un- 
sanitary conditions,  and  the  more  food  they  get,  the 
oftener  they  breed  and  the  more  young  they  have  in 
each  litter.  Therefore,  food  should  be  kept  where  they 
cannot  reach  it  and  all  garbage  kept  in  metal  containers. 
The  liberal  use  of  cement  for  foundations  and  floors  and 
strong  wire  netting  over  basement  windows  and  the 
ends  of  drain  pipes,  is  a  great  help  in  keeping  them  out. 

Two  forms  of  White-footed  Mice  are  very  common 
here,  one  inhabiting  the  woods,  known  as  the  Northern 
White-footed  Mouse,  and  the  other,  the  Prairie  White- 
footed  Mouse,  living  in  the  open  fields  as  its  name  im- 
plies. The  woodland  form  is  light  brownish  in  color 
with  pure  white  underparts,  while  the  prairie  one  is 
of  a  darker  color  and  is  smaller  with  a  somewhat 
shorter  tail.  Both  have  large  ears  and  big  black  shoe- 
button  eyes. 

The  Northern  White-footed  Mouse  makes  its  home 
in  hollows  of  trees  or  roofs  over  a  bird's  nest  and  lines 
it  with  grass.  It  will  even  dispossess  birds  of  an  oc- 
cupied nest  and  sometimes  eat  the  eggs  or  young.  The 
diet  of  these  mice  is  mainly  vegetarian,  consisting  of 

[138] 


Mammals  of  the  Chica'^^o  Area  U 

nuts,  fruit  and  bark.  In  the  fall,  they  commonly  resort 
to  grain  fields.  They  also  like  meat  when  it  can  be 
found.  One  that  I  caught  in  a  trap  was  half  eaten  by 
its  fellows.  They  store  up  grain  and  nuts  for  the  win- 
ter in  hollows  or  bury  them  in  holes  and  stumps  under 
logs  where  they  sometimes  make  their  nests.  Once 
my  dog  brought  me  a  tin  can  in  which  a  mouse  of  this 
species  had  four  half  grown  young  of  a  slaty  gray 
color.  Another  time,  in  a  cabin  in  the  woods,  I  found 
that  a  female  had  made  a  nest  of  cotton  in  my  shoot- 
ing coat  pocket  and  had  five  newly  born  young  there. 
The  young  number  from  three  to  six  and  two  or  three 
litters  are  born  each  season.  In  winter,  as  many  as 
a  dozen  live  together,  separating  in  the  spring  to  make 
their  nests  and  rear  their  j^oung. 

The  Prairie  White-footed  Mouse,  living  away  from 
trees,  must  of  a  necessity  make  its  home  under  ground ; 
here  it  winters  and  the  first  litter  is  born.  As  the 
weather  becomes  warmer,  and 
the  long  grass  affords  protec- 
tion, it  lives  more  above  ground 
under  old  logs,  stones  or  fences. 
In  the  fields  it  lives  on  insects, 
leaves  of  certain  plants  and 
weed  seeds.   During  the  fall  it  ''^^ 

is  found  in  the  shocks  of  corn  and  other  grain  and  in 
the  winter  it  often  causes  great  damage  by  burrowing 
under  young  fruit  trees  and  eating  the  bark  from 
the  roots.  The  average  number  of  young  is  five,  and 
they  have  been  found  during  every  month  from  March 
to  November.  Like  its  woodland  cousin,  it  stores  up 
quantities  of  food  for  winter,  but  it  lives  in  pairs  only 
in  the  winter  burrows. 

Two  forms  of  meadow  mice  or  voles  also  occur 
here,   the   Common   Meadow  Mouse   and   the   Prairie 

[  139  ] 


12  Field  Museum  of  Natural  History 

Meadow  Mouse.  They  are  of  a  stockier  build  than  the 
White-footed  Mice  and  have  shorter  ears  and  tails. 
The  Common  Meadow  Mouse  lives  in  marshes,  damp 
pastures  and  boggy  woods.  It  is  a  dark  grayish  ani- 
mal, lighter  on  the  sides  and  lighter  gray  underneath. 
Living  in  such  wet  places,  it  is  naturally  forced  to 
live  above  ground  most  of  the  time  and  to  make  its 
nests  in  tussocks  of  grass  or  in  very  shallow  burrows 
above  the  damp  ground.     The  young  number  five  or 

six  and,  sometimes,  eight,  and 
three  litters  are  born  each  sea- 
son. Meadow  mice  are  active 
throughout  the  year.  In  winter 
they  live  under  the  snow  in  nests 
'^  of  grass  which  are  also  used  as 
store  houses  and  are  filled  with  grass  and  weed  roots, 
grain  and  bark.  Even  living  as  they  do,  under  the  grass 
in  summer  and  under  a  blanket  of  snow  in  winter,  many 
cannot  escape  the  sharp  eyes  of  hawks  and  owls  that 
continually  prey  upon  them.  Those  living  near  a 
stream  or  pond  are  as  much  at  home  in  the  water  as 
on  land,  and  often  use  it  as  a  means  of  escape  when 
pursued. 

The  Prairie  Meadow  Mouse  or  Prairie  Vole  has 

many  of  the  same  habits  and  tastes  as  the  preceding 
species,  but,  since  it  prefers  high  and  dry  ground,  its 
manner  of  living  is  naturally  not  the  same.  It  is  of 
a  slightly  lighter  color  with  a  more  grizzled  appear- 
ance, and  the  underparts  are  more  buffy  than  gray. 
Inhabiting  dry  fields,  it  is  able  to  burrow  and  live 
under  ground  during  the  winter,  bringing  forth  its  first 
litter  of  young  there.  The  burrows  contain  store- 
rooms with  provisions  for  winter,  such  as  small  bulbs 
and  grass  roots.  Grain  also  forms  a  large  part  of  its 
diet.  When  it  encounters  roots  of  fruit  trees  in  its 
burrowing,  it  eats  the  bark  and  often  kills  the  tree. 

[140] 


Mammals  of  the  Chicago  Area  13 

A  mouse  closely  related  to  the  Meadow  Mouse  is 
the  Pine  Mouse  or  Mole  Mouse,  but  it  is  very  rare  in 
this  region,  only  four  having  been  recorded.  It  is 
smaller  than  either  of  the  meadow  mice  and,  although 
it  has  the  same  general  form,  it  has  softer  and  silkier 
fur.  The  habit  of  making  many  burrows  under  the 
ground  where  it  lives  most  of  the  time,  has  earned  it 
the  name  of  Mole  Mouse. 

The  largest  member  of  the  rat  and  mouse  family 
is  the  Muskrat,  one  of  our  important  fur-bearers.  In 
spite  of  the  war  waged  against  it,  it  still  makes  its 
home  close  to  man  and  his  works.  Muskrats  are  fairly 
common  about  Chicago.  They  were  especially  numer- 
ous, a  few  years  ago,  in  the  lagoons  of  Jackson  Park. 
Man  is  really  its  only  enemy,  since  he  has  driven  out 
the  Otter  and  greatly  thinned  the  ranks  of  the  Mink. 
It  lives  chiefly  in  burrows  in  or  under  banks,  the  en- 
trance being  under  water  and  the  passage  slanting  up 
to  a  large  chamber  above  the  level  of  the  water.  It 
also  builds  large  houses  of  reeds  and  weed  stalks  with 
an  entrance  under  water.  The  food  consists  of  fresh- 
water mussels  and  aquatic  plants.  It  does  a  good  deal 
of  damage  to  water-lilies  in  parks.  One  reason,  per- 
haps, why  the  muskrat  is  able  to  live  on  among  men 
is  that,  during  the  winter  when  the  ponds  are  frozen, 
it  can  move  about  freely  under  the  ice  in  search  of 
food  and  yet  cannot  be  seen.  When  there  is  space  be- 
tween the  water  and  the  ice,  it  can  breathe  there,  and 
can  always  get  air  near  the  thin  ice  along  the  shore. 
One  litter  of  from  five  to  seven  young  is  raised  each 
year.  The  flesh  of  the  muskrat  is  said  to  be  very  pal- 
atable either  boiled  or  roasted. 

One  of  our  most  interesting  but,  unfortunately, 
most  uncommon  mice,  is  the  Jumping  Mouse.  It  is  a 
little  tawny-colored  animal  with  medium-sized  ears  and 
very  long  hind  feet  and  a  four  and  a  half  inch  tail 

■      [  141  ] 


14 


Field  Museum  of  Natural  History 


which  is  fully  an  inch  longer  than  its  body.  It  is  said 
to  be  able,  when  frightened,  to  make  jumps  of  ten  feet 
in  its  effort  to  escape.  In  the  summer,  it  is  apt  to  be 
met  with  in  this  area,  mainly  in  cool  places  either  in 
the  woods  or  fields.    It  spends  the  cold  months  asleep. 


rolled  into  a  tight  little  ball  in  its  nest  under  ground. 
Nests  of  grass  and  leaves  are  also  constructed  on  the 
ground  for  summer  use,  where  the  three  to  six  young 
are  sometimes  born. 

Rabbits,  although  formerly  in  the  order  Rodentia, 
have  now  been  separated  and  placed  in  the  order  Lago- 
morpha.  The  members  of  this  order  are  closely  related 
to  the  Rodentia,  but  among  other  differences,  have 
four  upper  incisors  instead  of  two.  The  second  pair  is 
very  small  and  is  placed  behind  the  front  ones.  Our 
representative  is  the  Cotton-tail  Rabbit  which  is  so 
common  in  all  the  Chicago  suburbs.  It  does  a  good 
deal  of  damage  to  suburban  gardens  in  summer  and  to 
trees  and  bushes  in  winter.  It  seems  to  be  more  com- 
mon about  small  towns  than  in  the  open  country  where 
hunting  is  permitted.  It  lives  in  small,  wooded  areas 
and  brushy  fields,  feeding  on  grass,  leaves  and  buds  in 
the  summer  and  mainly  on  bark  in  the  winter.  Piles 
of  brush  cut  in  the  fall  often  have  all  the  bark  stripped 
from  the  small  branches  and  twigs  by  spring.    Three 

[142] 


Mammals  of  the  Chicago  Area  15 

litters  are  raised  each  season,  the  first  one  coming  very- 
early  in  the  spring,  I  once  found  five  young  rabbits  in 
their  cup-shaped  hollow  under  a  brush  pile  early  in 
March  while  snow  still  covered  the  ground.  The  young 
stay  with  the  mother  only  about  a  month,  when  they 
start  out  for  themselves,  and  are  often  found  in  the 
woods  and  fields.  I  remember  a  large  mastiff  that 
used  to  bring  them  to  us  in  his  mouth,  alive  and  un- 
harmed. Rabbits  rely  on  staying  quiet  to  escape  notice 
and  will  not  move  until  literally  stepped  on ;  then  they 
race  off  with  great  bounds,  their  little  powder-puffs  of 
tails  bobbing  up  and  down  as  they  go.  The  larger 
mammals,  birds  of  prey,  and  man,  all  hunt  the  rabbit 
and,  were  it  not  so  prolific,  it  would  soon  be  extermi- 
nated. 

The  order  Carnivora  comprises  the  flesh-eating 
mammals,  mainly  beasts  of  prey,  as  the  dogs,  cats, 
weasels  and  coons.  The  larger  ones,  such  as  the  wolves, 
bears  and  cats,  are  soon  driven  out  of  a  settled  district. 
The  largest  mammal  of  this  region  is  still  with  us  only 
because  it  has  developed  a  cun- 
ning and  shrewdness  rarely 
equalled  among  other  mammals. 
This  is  the  Red  Fox  which, 
while  seen  occasionally  in  other 
localities,  is  practically  confined 
here  to  the  Dune  Region  of 
northern  Indiana,  The  fox,  like 
the  muskrat,  has  benefited  by  man's  driving  out  its  en- 
emies, and,  as  it  can  nearly  always  outwit  man,  it  is 
fairly  safe.  If,  however,  a  fox  raids  too  many  chicken 
coops,  there  is  sure  to  be  a  hunt  organized  and  the  thief 
will  be  hunted  down  and  destroyed.  If  it  confines  itself 
to  such  food  as  mice,  grasshoppers,  muskrats,  rabbits, 
and  to  wild  grapes  and  other  fruits,  its  presence  is 
seldom  suspected.    The  fox  makes  its  den  in  holes  in 

[143] 


16  Field  Museum  of  Natural  History 

the  ground,  some  natural  cavity  in  the  rocks  or  in 
hollow  stumps.  One  litter  of  four  to  eight  young  is 
born  each  year  in  April, 

One  other  large  mammal,  the  Coyote  or  Prairie 
Wolf,  is  occasionally  reported  in  this  region.  It  is  prob- 
able that  some  of  these  reports  are  based  on  pure-bred, 
fully  wild  coyotes,  but  actual  specimens  with  skulls  are 
usually  needed  to  prove  whether  or  not  they  refer  to 
wild  or  half  wild  dogs  or  animals  escaped  from  cap- 
tivity. The  body  of  one  killed  near  Waukegan,  in 
December,  1924,  showed  very  plainly  how  it  is  re- 
ceived in  a  settled  area,  for  it  contained  all  sizes  of 
shot,  some  which  it  must  have  carried  for  nearly  three 
years.  While  the  skin  was  large,  it  appeared  to  be 
almost  pure  coyote,  but  the  skull  showed  that  it  was 
not  pure-blooded,  but  probably  had  a  strain  of  domestic 
dog  in  its  ancestry.  Coyotes  are  especially  destructive 
to  sheep  and,  in  some  parts  of  the  west,  sheep-raising 
is  seriously  handicapped  by  them.  They  have  a  cun- 
ning equal  to  or  perhaps  greater  than  that  of  the  fox 
and  are  well  able  to  hold  their  own  when  the  odds  are 
not  too  strong  against  them.  So  a  constant  warfare 
must  be  kept  up  to  keep  their  numbers  below  the 
danger  point. 

The  Skunk  is  a  very  attractive  looking  animal,  but 
it  is  another  case  of  fine  feathers  not  making  fine  birds, 

for  when  molested  or  angry,  it 
ejects  a  strong,  nauseating  fluid 
which  makes  the  vicinity  for  at 
least  a  quarter  of  a  mile  about  most 
untenantable.  The  skunk's  motto 
is,  however,  "Let  me  alone  and  I'll 
let  you  alone,"  so  if  not  molested,  it 
goes  quietly  on  its  way  in  search  of  bugs  and  beetles. 
Its  menu  varies  from  chickens'  eggs,  young  mice,  birds 

[144] 


Mammals  of  the  Chicago  Area  17 

and  snakes  in  the  early  spring  and  summer,  to  beetles 
and  grasshoppers  in  the  fall.  When  food  becomes  scarce 
in  the  fall,  skunks  hole  up  until  the  warm  days  of  Feb- 
ruary. They  also  live  under  barns,  sheds,  and  old  farm 
buildings.  The  young  are  born  early  in  May  and  num- 
ber from  four  to  six.  The  scent  glands  can  be  removed 
from  the  animal,  making  it  harmless,  and  this  is  gen- 
erally done  on  fur  farms,  so  the  fur  will  not  have  the 
disagreeable  odor  on  damp  days.  The  odor  is  noticea- 
ble for  a  number  of  years  in  the  hair  of  dogs  that  have 
killed  skunks,  especially  when  the  dogs  are  wet.  Some 
Horned  Owls  have  a  strong  odor  of  skunk,  as  they  often 
kill  them  for  food.  People  who  have  eaten  the  flesh  of 
this  animal  claim  that  it  has  a  very  fine  flavor  and  that 
it  reminds  one  of  chicken.  The  ranges  of  the  Northern 
Skunk  and  the  Illinois  Skunk  meet  in  this  area,  so  it  is 
hard  to  say  to  which  sub-species  our  skunks  belong. 
Most  of  them  are  intergrades  between  the  two  and 
could  be  referred  to  either.  In  the  Dune  Region,  it 
also  intergrades  with  the  Eastern  Skunk. 

A  valuable  fur-bearer  still  occasionally  met,  is  the 
Mink.  It  might  be  termed  a  water  weasel,  for  it  is 
generally    found    near    the 

water  and  part  of  its  food  ^^     k 

consists  of  fish,  frogs,  cray-  ^^^^^^     \  L 

fish  and  other  aquatic  ani-  ^^^^^^'^f 

mals  including  the  muskrat.  ^^^^^^ __,^j:^ ^^  ^ 
Although    it    prefers    the  ^^^^^^^^==^ 

water,  it  is  as  much  at  home 

on  land.  Its  swiftness  even  enables  it  to  catch  squir- 
rels and  rabbits.  It  also  eats  many  meadow  mice  and 
farmers'  chickens  or  other  poultry  when  it  can  get 
them.  Young  birds  and  eggs  are  destroyed  and,  in 
fact,  anything  in  the  shape  of  meat,  since  it  never  eats 
any  vegetable  matter.  It  lives  singly  and  is  seldom 
found  in  pairs  except  during  the  mating  season.     The 

[145] 


18  Field  Museum  of  Natural  History 

young  are  born  in  April  or  May  in  a  burrow  or  hollow 
under  an  old  log,  and  stay  with  the  female  until  nearly 
grown,  when  they  gradually  wander  away  and  find  new 
homes  for  themselves.  The  mink  is  of  dark  brown 
color  with  a  patch  of  white  on  the  chest  and,  unlike  its 
relatives,  the  weasels,  it  does  not  turn  white  in  winter. 

Only  one  weasel  is  known  to  occur  here  in  any 
numbers,  and  it  is  only  locally  common.  This  is  the 
New  York  Weasel,  which  is  a  long,  slim  animal,  vary- 
ing from  twelve  to 
sixteen  inches  i  n 
length.  The  female 
is  much  smaller 
than  the  male.  In 
summer,  it  is  dark 
brown  with  white  underparts,  and  in  winter,  the  whole 
animal  turns  white.  The  white  is  often  tinged  with 
yellow.  The  end  of  the  tail  is  black  in  both  winter 
and  summer  pelages.  Bonaparte's  and  Least  Weasels 
have  been  taken  in  southern  Wisconsin  and,  therefore, 
are  likely  to  be  found  here.  They  are  smaller,  and  the 
Least  Weasel  lacks  the  black  tip  on  the  tail.  All  the 
weasels  are  ferocious  and  blood-thirsty  little  animals, 
many  times  killing  for  the  pure  joy  of  it  even  when  not 
prompted  by  the  pangs  of  hunger.  At  such  times  they 
only  suck  the  blood  and  eat  the  brains  of  their  victims. 
Farmers  have  lost  as  many  as  fifteen  or  twenty  fowls 
in  a  single  night  in  this  manner.  These  cases  are  the 
exception,  however,  for  meadow  mice,  wood  mice, 
ground  squirrels,  rabbits  and  other  small  mammals 
are  their  usual  food,  and  in  this  way  they  are  a  great 
benefit  to  the  farmers.  Like  the  mink,  they  live  singly 
except  in  the  breeding  season,  and  the  young  stay  with 
the  mother  until  late  in  the  fall.  These  number  from 
five  to  eight. 

[146] 


Mammals  of  the  Chicago  Area 


19 


In  the  more  wooded  districts,  especially  in  the 
river  bottoms,  the  Raccoon  is  sure  to  be  found.  Its 
home  in  this  region  is  generally  in  some  hollow  tree, 
although  I 
have  known  it 
to  live  under 
barns.  The 
coon  usually 
wanders 
about  at 
night,  either 
up  in  the  trees 
hunting  birds' 

o  r    squirrels' 

nests,  or  along  the  shores  of  creeks  and  streams,  looking 
for  frogs,  crayfish  and  other  aquatic  animals.  Green 
corn  is  one  of  its  favorite  foods  and  it  is  apt  to  do  much 
damage,  tearing  down  much  more  than  it  can  eat.  When 
it  gets  into  a  hen  roost,  it  also  kills  more  than  it  needs 
and  returns  the  next  day  for  more,  which  is  very  often 
its  undoing,  A  coon  makes  an  intelligent  and  interesting 
pet.  It  has  a  curious  habit  of  washing  all  meat  before 
eating  it,  and  captive  coons  have  been  known  to  refuse 
to  eat  when  no  pan  of  water  was  provided  for  them. 
The  young  number  from  three  to  six,  and  are  born  in 
April  and  May  and  stay  with  the  parents  for  some 
time.  When  cold  weather  comes  on,  the  whole  family 
rolls  up  in  the  nest  and  takes  cat-naps  all  winter,  ap- 
pearing now  and  then  on  warm  days. 

The  order  Insectivora  includes  the  shrews  and  moles 
which,  like  the  Carnivora,  live  on  animal  food,  but  in  the 
shape  of  insects  and  worms.  Our  smallest  mammal 
is  the  Common  or  Long-tailed  Shrew,  its  body  being 
only  two  and  a  half  inches  long  and  its  tail  an  inch 
and  a  half  long.  It  makes  its  home  under  old  logs,  tree 
roots  and  bunches  of  grass,  in  the  woods  and  fields, 


[147] 


20  Field  Museum  of  Natural  History 

mainly  in  cool  places.  It  is  a  very  active  little  animal, 
moving  so  rapidly  the  eye  can  scarcely  follow  it  among 
the  brown  leaves  which  it  closely  resembles  in  color. 
It  is  like  the  weasel  in  its  ferocity  and  bloodthirstiness. 
Dr.  C.  H.  Merriam  tells  of  three  he  placed  together  in 
a  large  tumbler.  One  was  at  once  killed  and  devoured, 
and  eight  hours  later,  one  of  the  others  had  been  eaten, 
and  the  remaining  one  with  two  of  his  kind  and  size 
inside  him,  was  greatly  extended  by  his  day's  meal. 
But  little  is  known  of  its  home  life  and  young. 

Besides  this  little  fellow,  a  larger  shrew  is  found 
here,  the  Short-tailed  or  Mole  Shrew.  This  shrew 
lives  in  burrows  and  is  continually  making  new  ones 
in  all  directions  in  its  hunt  for  insects,  ground 
beetles  and  their  larvae.  Combined  with  this  mole- 
like habit,  its  very  small  eyes  and  hardly  noticeable 
ears  under  the  fur  have  helped  to  give  it  the  name  of 
Mole  Shrew.  It  is  just  as  ferocious  as  its  smaller 
cousin,  but,  being  almost  twice  its  size,  can  prey  upon 
young  mice  and  birds,  and  has  been  known  to  kill  mice 
larger  and  heavier  than  itself.  All  shrews  have  glands 
that  permit  them  to  emit  a  very 
strong,  musky  odor,  and  for  that  rea- 
son, although  they  may  be  killed,  they 
are  eaten  by  but  few  animals,  owls 
and  weasels  being  the  only  ones  to 
which  they  are  welcome.  Shrews  do 
not  hibernate  but  are  active  all  winter.  The  Small 
Short-tailed  Shrew,  which  is  about  an  inch  and  a  half 
shorter  than  the  preceding  species,  has  been  recorded 
from  this  area  but  once.  Dr.  M.  W.  Lyon,  Jr.,  took  a 
single  specimen  near  Tremont,  Indiana,  in  the  fall  of 
1924.  The  known  range  of  this  shrew  just  reaches  our 
southern  limits,  but  after  more  work  has  been  done 
here,  it  will  no  doubt  be  found  to  include  most  of  this 
region. 

[148] 


% 


MAMMALS  OF  THE  CHICAGO  AREA. 

PART  OF  AN   EXHIBIT  IN   FIELD  MUSEUM  OF  NATURAL  HISTORY. 


Mammals  op  the  Chicago  Area  21 

Two  Moles  have  been  recorded  from  this  region, 
the  Prairie  and  the  Star-nosed  Mole,  but  the  latter  is 
very  rare  here.  The  Prairie  Mole  is  a  stocky  animal 
about  six  inches  long  with  enormous  fore-feet  which 
at  once  identify  it.  It  lives  under  ground  most  of  its 
life,  forming  many  yards  of  tunnels  in  its  search  for 
the  slugs,  worms  and  larvae  on  which  it  feeds.  When 
in  captivity,  it  will  eat  meat.  During  the  winter  it 
digs  deeper  into  the  earth  beyond  the  frozen  ground 
for  its  food.  The  ground  is  raised  in  a  ridge  when  the 
tunnels  are  made  close  to  the  surface  and  these  give 
the  trapper  the  clue  as  to  areas  inhabited  by  moles. 
The  skin  of  the  eastern  moles,  while  equaling  that  of 
the  European  mole,  is  not  so  large  or  fine  as  that  of 
those  found  on  the  Pacific  ^.^^fe^. 

Coast.     At    all   times,    the  J^^^^^^^ 

runways  of  the  moles  are     _^C>-^^^^^^^^^ 
used    by    other    mammals,     ^c^^^'^^^^^^S^^^ 
such  as  meadow-mice,  pine  fj^^^^E-^^""^  ^^ 

mice  and  shrews,  and  the 

moles  are  unjustly  blamed  for  the  damage  they  do  to 
plants  and  trees.  The  nest  is  a  large  mass  of  leaves 
and  grass  from  six  to  eighteen  inches  below  the  ground. 
The  mole  produces  two  litters  a  year  of  from  two  to 
four  young  each. 

The  Star-nosed  Mole  is  about  the  same  size  as  the 
preceding  species,  but  the  feet  are  not  nearly  so  large. 
It  has  numerous  fleshy  projections  on  the  end  of  the 
snout  that  are  used  as  feelers  and  from  which  it  gets 
its  name.  This  mole  lives  near  the  water  and  in  damp 
boggy  marshes  and  woods.  But  few  of  its  nests  have 
been  found,  and  they  were  situated  like  those  of  the 
Prairie  Mole,  nearly  a  foot  under  ground.  The  Star- 
nosed  Mole  is  active  throughout  the  year  and  appears 
above  ground  more  than  any  other  species,  even  in 
winter.  The  Chicago  area  is  on  the  edge  of  its  range, 
which  is  to  the  north  and  east,  so  it  is  quite  rare  here. 

[149] 


22 


Field  Museum  of  Natural  History 


But  one  family,  the  Vespertilionidae,  is  represented 
here  from  the  order  of  Bats  or  Chiroptera.  Seven  spe- 
cies of  this  family  have  been  recorded  from  this  area. 

Five  of  them,  the  Brown,  Little 
Brown,  Red,  Hoary  and  Silver- 
haired  are  common,  and  there  is 
one  record  each  for  Say's  and 
Rafinesque's  bats.  They  are 
purely  insectivorous,  hunting 
from  sunset  till  dark  and  in  the 
early  hours  of  dawn.  They  live 
in  caves,  hollow  trees,  attics  and 
crannies  of  old  houses  and  in  any 
holes  where  it  is  dark  and  they  can  sleep  during  the 
day.  Some  of  them  migrate  in  the  fall  and  others  re- 
main to  hibernate.  Like  birds,  they  follow  the  water 
courses  in  their  migrations  and  during  the  fall  many 
are  picked  up  in  and  about  the  Museum  building.  The 
young,  numbering  from  two  to  four,  go  with  the  mother 
on  her  hunting  trips,  clinging  to  her  breast  when  small. 
When  too  large  for  this,  they  are  left  in  some  hidden 
place  to  be  called  for  later.  They  are  among  our  most 
useful  animals  and  deserve  all  the  encouragement  and 
protection  possible. 


The  Virginia  Opossum  is  the  only  representative 
of  the  Order  Marsupiala  found  in  this  area.  Like  most 
of  the  other  members  of  this  order,  the  female  carries 


[150] 


Mammals  of  the  Chicago  Area  23 

the  young  in  a  pouch  for  a  number  of  weeks  after  they 
are  born.  Here  they  feed  and  grow  until  ready  to 
come  out  and  travel  with  their  mother.  Opossums  have 
prehensile  tails  and  their  feet  are  like  hands,  so  they 
can  climb  about  in  trees  with  nearly  the  ease  of  a 
monkey.  They  are  practically  omnivorous  in  their 
diet.  They  have  been  recorded  in  this  region  during 
the  past  fifteen  years  only  from  the  Dunes  where  they 
are  occasionally  seen. 

Colin  C.  Sanborn, 
Assistant,  Division  of  Mammals. 


In  the  alcoves  just  west  of  Pullman  Hall  are  four  groups  of 
Chicago  mammals.  Seven  species  are  shown  with  their  natural 
surroundings.  One  shows  the  Muskrat  and  its  house  built  in  the 
water;  one,  the  Woodchuck  with  young  ones,  enjoying  a  few 
moments  outside  the  entrance  to  its  burrow;  one,  the  Red  Squir- 
rel, hunting  about  in  the  leaves ;  and  one,  the  Short-tailed  Shrew, 
Meadow  Mouse,  Northern  White-footed  Mouse,  and  Jumping 
Mouse,  in  their  natural  habitats,  of  wood,  field  and  marsh.  There 
is  also  a  temporary  screen  in  Stanley  Field  Hall,  showing  nearly 
all  the  Chicago  mammals. 


[151] 


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